FDA gives full approval for Keytruda in head and neck squamous cell carcinoma

Merck Inc announced that the FDA has approved Keytruda (pembrolizumab), Merck’s anti-PD-1 therapy, as monotherapy in patients whose tumors express PD-L1 (Combined Positive Score [CPS] at least 1) or in combination with platinum and fluorouracil (FU), a commonly used chemotherapy regimen, for the first-line treatment of patients with metastatic or with unresectable, recurrent head and neck squamous cell carcinoma (HNSCC). The approval is based on results from the pivotal Phase III KEYNOTE-048 trial, where Keytruda demonstrated a significant improvement in overall survival (OS) compared with the EXTREME regimen (cetuximab with carboplatin or cisplatin plus FU), a standard treatment, as monotherapy in patients whose tumors expressed PD-L1 (CPS at least 1) (HR=0.78 [95% CI, 0.64-0.96]; p=0.0171) and in combination with chemotherapy in the total study population (HR=0.77 [95% CI, 0.63-0.93]; p=0.0067).

With these new indications, Keytruda is the first anti-PD-1 therapy approved in the first-line setting as monotherapy in patients whose tumors express PD-L1 (CPS at least 1) or in combination with chemotherapy regardless of PD-L1 expression for patients with metastatic or with unresectable, recurrent HNSCC and the first anti-PD-1 therapy to demonstrate a statistically significant improvement in OS in these patients.

Comment: Keytruda was initially approved for the treatment of patients with recurrent or metastatic HNSCC with disease progression on or after platinum-containing chemotherapy in 2016 under the FDA’s accelerated approval process based on objective response rate data from the Phase Ib KEYNOTE-012 trial. In accordance with the accelerated approval process, continued approval was contingent upon verification and description of clinical benefit, which has now been demonstrated in KEYNOTE-048 and has resulted in the FDA converting the accelerated approval to a full (regular) approval.